Heat treatment apparatus for a travelling yarn or yarns



KOSAKU ISOBE ET AL 3,449,549

June 10, 1969 HEAT TREATMENT APPARATUS FOR A TRAVELLING YARN OR YARNS I of5 Sheet Filed March 27. 1967 Junie 10, 1969 KQSAKU ISOBE ET AL 3,449,549

HEAT TREATMENT APPARATUS FOR A TRAVELLING YARN OR YARNS Filed March 27, 1967 Shee't 2 0! 5 Fig. 33 I436 4 lb 10 P L1 FM IHHHJIII /0 f F x? r mmlm June 10, 1969 KQSAKUJSQBE ET AL 3,449,549

HEAT TREATMENT APPARATUS FOR A TRAVELLING YARN 0R YARNS Filed March 27, 1967 Sheet 3 of 5 June 10, 1969 KOSAK UV ISOBE ET AL 3,449,549

HEAT TREATMENT APPARATUS, FOR A TRAVELLING YARN OR YARNS Shee t Filed March 27, 1967 June 10, 1969 KQ'SAKU soaE ET AL 3,449,549

[HJJAT TREATMENT APPARATUS FOR A TRAVELLTNG YARN OR YARNS I Filed March 27. 1967' Sheet 5 of s 7 Temperature Fig. 9

- Distance from the top United States Patent Japan Filed Mar 27, 1967, Ser. No. 626,151 Claims priority, application Japan, Mar. 29, 1966, 41/123,948; Nov. 2, 1966, 41/71,935 Int. Cl. D023 13/00 U.S. Cl. 219-388 Claims ABSTRACT OF THE DISCLOSURE A heat treatment apparatus for heat treating of a travelling yarn or yarns by utilizing infra-red rays which are radiated from a fil-m radiator of high polymer deposited on the surface of at least one deep groove of a heated cylinder.

This invention relates to heat treatment of yarns and more particularly to apparatus for heat treating a travelling yarn or yarns and most particularly to apparatus employing infra-red rays.

In the manufacturing of high polymer yarns (highly polymerized components), such as twisted nylon yarns, it is necessary to carry out heat treatment of the travelling yarn or yarns under a tensible force. In conventional techniques, the heat treatment of travelling yarn is generally carried out in the following conditions: 1) the travelling yarn is twisted under a tensible force; (2) the yarn travels at a high speed (e.g., 60 meters/minute); (3) the travelling yarn is contacted during a period of time (0.5 to 0.8 second) with the surface of a metal plate heated at about 185 C.

In the conventional method, however, the travelling yarn is directly contacted with the surface of the heated metal plate. As the result of this condition, molten fibers and oily matter on the travelling yarn are liable to be strongly adhered to the surface of the heated metal plate. Accordingly, the thermal conductivity from the heated surface to the travelling yarn is considerably diminished; the friction force between the travelling yarn and the surface of the heated metal plate increases; and the travelling yarn is damaged on account of the lack of smoothness of the surface of the heated plate. If such adhesion occurs on the surface of the heated plate, it is considerably troublesome to remove the adhered materials since the heated plate has to be cooled before cleaning and chemicals must be used for cleaning. In this case, the chemicals cause frequently erosion of the surface of the metal plate and of the heaters or heating elements made of Nichrome wire.

As mentioned above, it is difiicult to maintain the desired smoothness of the surface of the heated metal plate, and the life of the metal plate becomes shorter due to the uneven wear of the plated surface of the metal plate. Moreover, the yarn made by conventional devices has the lack of uniformity as to the mechanical characteristics, such as tensile strength, and the stability of crimps, etc. Accordingly, the cloth woven from such yarn is liable to have unevenness of dying. In addition to such disadvantages, it cannot be avoided that a considerable amount of temperature gradient appears between the surface and inside of the travelling yarn in accordance with an increase of the diameter of the travelling yarn. Accordingly, the surface of the travelling yarn is liable to be overheated during the heat treatment thereof.

Furthermore, the power consumption of the conventional apparatus is considerably large.

In view of the above-mentioned problems it is known that the heat treatment process or step in making yarns to obtain homogeneity of yarns and that heat treatment apparatus, in which the quick-and-simple cleaning of the heater plate can be carried out without the use of chemicals, is badly needed.

A principle object of this invention is to provide a heat treatment apparatus capable of carrying out uniform heat treatment of travelling yarn or yarns by a relatively small power consumption.

Another object of this invention is to provide .a heat treatment apparatus for treating travelling yarn or yarns having a longer working life than conventional heat treatment apparatus.

Still another object of this invention is to provide a heat treatment apparatus for treating travelling yarn or yarns capable of being easily maintained.

These objects and other objects of this invention can be attained by a heat treatment apparatus of a travelling yarn or yarns of this invention, provided with a thermal conductor heated by electrical heaters, characterized in that the thermal conductor is a cylinder of thermally conductive material, such as aluminum, which is provided with, along the axial direction of the cylinder, a plurality of shallow grooves and at least one deep groove with U-shaped cross-section to guide the travelling yarn. Electrical heaters are arranged insulatively in the plurality of shallow grooves. A film radiator of infra-red rays is deposited on the internal surface of the deep groove by the backing finish of high polymer containing at least one substance capable of radiating infra-red rays, that the cylinder is surrounded, except the deep groove, by use of heat resisting material so as to form a yarn guide along the deep groove.

A feature of this invention is a plug of heat resisting material provided to be coupled with the guide to avoid the loss of heat from the cylinder.

The novel features of this invention are set forth with particularity in the appended claims, however this invention, as to its construction and operation together with other objects and advantages thereof, may best be understood by reference to the following description, taken in connection with the accompanying drawings, in which the same parts are designated by the same characters, numerals and symbols as to one another, and in which:

FIGURE 1A is a perspective view of a cylinder used in the apparatus of this invention;

FIGURE 1B is a cross-section view of the cylinder of FIG. 1A;

FIGURE 2A is a plane view of a disc coupled to either of both ends of the cylinder;

FIGURE 2B is a sectional view of the disc taken along a section line II II FIGURE 3A is a view of an end of the cylinder and one of two discs coupled to each other;

FIGURE 3B is a plan view of the cylinder and two end discs of the type shown in FIGURE 3A coupled together;

FIGURE 4A is a view of an end of another embodiment of the invention;

FIGURE 4B is a fragmentary plan view of the embodiment shown in FIGURE 4A;

FIGURE 5 is a cross-section of the embodiment of the invention;

FIGURE 6 is an enlarged cross-section view of another cylinder to be used in the apparatus of this invention;

FIGURE 7 is a perspective view of a plug coupled in operation to the apparatus of the invention;

FIGURE 8 is a fragmentary perspective view of another cylinder used to the apparatus of the invention; and

FIGURE 9 is a characteristic curve illustrating the distribution of temperature along a path of yarn of the cylinder.

The principle of the invention will first be described and compared with the principle of the conventional yarn heat treating apparatus. Materials of high polymer, such as nylon yarn, have a characteristic of absorbing therein a considerable amount of infra-red rays. By way of example, the nylon-6 has a remarkable absorbing characteristic of infra-red rays which are included in wave length bands 6,0. to 10 and of the vicinity of 15p If a high polymer material absorbs the energy of infra-red rays, vibration of the molecules occurs in the material so that the temperature of the material rises. The present invention utilizes this principle of the increase of temperature.

On the contrary, in the conventional yarn heat treatment which is carried out in travelling the yarn on the surface of heated metal plate, this heated surface is smoothly polished as a glazed finish. The heated surface has almost no emission power for emitting infra-red rays. Accordingly, the heat treatment by use of conventional apparatus is substantially carried out by the conduction of heat only.

Since the heat treatment of this invention is carried out by utilization of the vibration of the molecules caused by the absorbing of infra-red rays the principle of this invention is quite dilferent from the principle of conventional apparatus.

Referring to FIGURES 1A and 1B, a cylinder 1 which is an important part of the apparatus of this invention and to be employed to heat travelling yarn as later described. The cylinder 1 is made of a thermally conductive material, such as aluminum or iron, etc., and provided with, on its surface and along its axial direction, a deep groove 2 and a plurality of shallow peripheral grooves 3. In case of a cylinder having a diameter of 15 millimeters and a length of 750 millimeters, by way of example, the cylinder 1 has, as shown in FIGURES 1A and 1B, six shallow grooves 3 each of which has a width of 1.5 millimeters and a depth of 3 millimeters. It is desirable that the depth of the deep groove 2 is slightly greater (e.g., 2 millimeters in case of the above example) than the radius of the cylinder 1. In each of the shallow peripheral grooves 3, an electrical heater 5, such as Nichrome (Ni (80 to 85%)Cr (15 to 20%)) wire, is inserted and held in an electrically insulated condition to heat the cylinder 1. A travelling yarn 4 passes longitudinally through the deep an electrically insulated condition to heat the cylinder 1. On the internal surface of the deep groove 2, a film radiator 6 for emitting infra-red rays is deposited. This film radiator 6 is formed on the internal surface by the backing finish of the material of high polymer which contains at least one substance capable of radiating infra-red rays. Fluorine resin (e.g., ethylene tetrafluoride) containing a small amount (e.g., 5%) of dispersed carbon black is desirable as the radiating material. It is more desirable that fluorine resin further contains fine grains of cadmium oxide and/ or ferric oxide (Fe O In an actual case, liquid fluorine resin containing a small amount of carbon black, cadmium oxide and/or ferric oxide is first spread on the surface of the deep slot 2 and then heated, for elfecting a finish, at a temperature of about 360 C. during a period of time of several minutes. As the result of the above-mentioned process a film radiator of a thickness (10 to 20p) for radiating infra-red rays is firmly formed on the internal surface of the deep groove 2. Moreover, if the high polymer material is molten and adhered on the film radiator, such adhered material can be easily removed from the film radiator by use of cloths and/or a brush while in a heated condition.

The cylinder 1 is further provided with a shallow groove 7 which is arranged on the surface and along the longitudinal direction of the cylinder as shown in FIGURE 1B. A thermoelectro converter (a temperature detector), such as a thermocouple or thermistor, is fixed in the shallow groove 7 so as to be easily coupled or decoupled. The converter is connected to an automatic temperature regulator which regulates the electric power supplied to the electric heaters 5 so that the cylinder 1 is heated at a predetermined stable temperature.

The cylinder 1 has, at both ends thereof, disc mounts or projections 8 each of which has a smaller radius than that of remainder of the cylinder 1.

Nichrome wires 5 are insulatively arranged in the respective shallow grooves 3 as mentioned above. In this case, the insulation material may be deposited on both or either of the shallow grooves 3 and/ or the Nichrome Wires 5. The insulated Nichrome wires 5 are inserted into the bottoms of the respective shallow grooves 3 and may be fixed by use of heat resisting cement dissolved in water glass.

If the cylinder 1 is made of aluminum, the surface of the cylinder 1 may be coated with alumite layer by utilizing the known art.

A disc 10 shown in FIGURES 2A and 2B is made of a heat resisting material, such as hard asbestos, and provided with a center hole 11 and a slit 12 along the radius of the disc 10. Two such discs 10 are coupled, respectively, with both ends of the cylinder 1 so that the center hole 11 is coupled with either of the disc projections 8 and the groove 12 coincides with the slit 2 of the cylinder 1.

The above-mentioned coupled condition of the cylinder 1 and the disc 10 is shown in FIGURES 3A and 3B. Terminals 16 and 17 are connected to the Nichrome wire 5 inserted in the shallow slots 3 to supply electric power thereto.

An outer tube 20, shown in FIGURES 4A and 4B which has a slit 21 along its longitudinal direction covers the outer side of the coupled disc 10 and the cylinder 1 so that the slit 21 coincides with both the slit 12 and the groove 2. This tube 20 is made of a thermal insulative material, such as hard vinyl chloride and fixed to the disc 10 by wood screws 24.

To guide the yarn 4 into the deep groove 2, guide plates 22a and 22b of heat resisting material, such as siliconlaminated plate, are arranged along both sides of the slits 21 (and 21) respectively and joined with metal plates 23a and 23b each having an L-shaped cross-section, as are shown in FIGURES 4A and 4B. The metal L-shaped plates 23a and 23b are fixed to the tube 20 by use of screws 25.

A space, separated by the two guide plates 22a and 22b and surrounded with the outer side of the cylinder 1, is formed inside the inner side of the tube 20 and inner sides of the two discs 10. Thermal insulation material 26 (e.g., glass fiber) fills this space as is shown in FIGURES 4B and 5.

A wedge-shaped plug 27 of heat resisting material is provided with, coupled with, the guide path between the guide plates 22a and 22b as shown in FIGURE 5.

In case of heat treatment of a travelling yarn in the apparatus of this invention mentioned above, the yarn 4 is inserted, through the guide path formed between the guide plates 22a and 22b, into the deep groove 2 and travels along substantially the axis of the cylinder 1. The wedge-shaped plug 27 is coupled to the guide path after insertion of the yarn 4 into the deep groove 2. Since the internal surface of the deep groove 2 is covered with the film radiator 6 which radiates infra-red rays, the film radiator 6 emits, effectively infra-red rays towards the travelling yarn 4 when the heaters 5 are heated by the electric power supplied from the terminals 16, 17. Moreover, the electric power can be regulated by an automatic temperature regulator controlled by a temperature detector inserted in the slit 7 of the cylinder 1. Air can be passed only through a limited space formed by the bottom of the deep groove 2 and the edge portion of the wedge-shaped plug 27. Accordingly, the travelling yarn 4 is uniformly and effectively heated in the deep" groove 2 by the small power consumption.

FIGURE 6 shows a cylinder 1 which is employed to carry out the heat treatment of two travelling yarns. In this example, the cylinder 1 is provided with two deep longitudinal grooves 2a and 2b which are arranged in parallel with each other and separated with a bulk head 28. The above-mentioned film radiator 6 is deposited on each of the internal surfaces of the deep grooves 2a and 2b. The remainder of the cylinder 1 is similar as that of the prior example described. Other parts of the apparatus are similar to the parts of the prior example. As shown in FIGURE 6, two yarns 4a and 4b travel respectively along centers of semicircles formed by the cross-sections of the deep grooves 2a and 2b.

FIGURE 7 shows another plug of this invention to be coupled to the guide path. This plug is formed by a sheet 30 of polyimid resin which is folded in two and joined at both overlapping end portions 31a and 31b of the sheet 30 so as to define a portion 32 in the form of an elliptical cylinder at the folded edge side. Heat resisting material, such as glass fiber, is filled in the tubular or cylinder portion 30. This plug is very light and does not easily crack. Moreover, polyimid resin is a good heat-resisting material having a little elasticity and operable over about 250 C. Accordingly, the power consumption of the apparatus can be considerably (e.g., 15%) reduced by the employment of this plug. If an aluminium film is deposited on the inner surface 35b of the sheet 30, the heat resisting effect of this plug is further increased since the aluminium film reflects effectively infra-red rays and the polyimid resin emits infra-red rays. Dusts or other matter adhered on the surface of the sheet can be easily removed.

The cylinder 1 of this invention may be provided with auxiliary heaters 5a and the end portions of the surface of the cylinder 1, as shown in FIGURE 8, to avoid the drop of temperature at the ends of the cylinder 1. In this example, a Nichrome fiat wire is arranged in zigzags on an insulation layer 40, such as glass tape, which is wound on the surface of the cylinder 1. This kind of auxiliary heater 5a. is fixed by use of glass tape 41, for example.'

The glass tape, positioned only on the deep groove 2 or grooves 2a and 2b, is cut off after the baking finish treatment at the temperature 360 C. to 380 C. Each of the resistances of the auxiliary heaters 5a is selected so as to assume a value 10% to of the total resistance of the heaters 5' and 5b. All the heater wires are connected in series.

FIGURE 9 shows the distribution characteristic curve 50 of the temperature, in the deep groove 2, along the length direction of the cylinder 1 which has a length of 600 millimeters and is positioned in a vertical position. Since the lower end of the cylinder 1 is cooled more than the top end of the cylinder on account of the cool air breathed into the deep grooves 2 by a chimney draft effect, it is desirable that the power consumption of the auxiliary heater 5a positioned at the lower end is larger than that of the auxiliary heater 5a positioned at the top end to equalize the temperature over all the length of the cylinder 1.

A result of an actual test of the apparatus of this invention is as follows:

(1) Condition (a) Yarn:

Two polyestal yarn of 75 denier; (b) Length of the cylinder:

60 centimeters; (c) Temperature of the surface of the deep groove (2a and 21b): 220 C.; (d) Room temperature:

C. (2) Result The power consumption of the apparatus was 45 watts by the use of the plug 27 (shown in FIGURE 5) and 40 6 watts by use of the plug shown in FIGURE 7. On the contrary, the power consumption of the conventional apparatus under the same condition is watts. If one yarn is to be treated, the power consumption is less than 5 watts, from the above values.

What we claim is:

1. A heat treatment apparatus for heat treating of a travelling yarn or yarns comprising, a heat conductive cylinder provided along the axial direction of the cylinder with a plurality of peripheral shallow grooves and at least one deep groove having a U-shaped cross section through which travelling yarn to be heat treated passes, insulated electrical heaters arranged in the plurality of shallow grooves; a film radiator for emitting infra-red rays deposited on the surface of the deep groove comprising a high polymer material containing, at least one substance capable of radiating infra-red rays; means for supporting both ends of the cylinder comprising heat resisting material; and heat resisting material surrounding the cylinder except along the deep groove so that the deep groove functions in operation as a guide for said travelling yam.

2. A heat treatment apparatus as claimed in claim 1, in which the apparatus is provided with a plug of heat resisting material coupled in operation with the guide to reduce loss of heat from the cylinder.

3. A heat treatment apparatus as claimed in claim 2, in which the plug is composed of a sheet of polyimid resin folded in two and joined at both overlapping end portions thereof so as to define a tubular portion of elliptical cylinder cross section, at a folded edge heat resisting material filling the tubular portion.

4. A heat treatment apparatus as claimed in claim 1, in which the film radiator is of fluorine resin which contains a small amount of dispersed carbon black.

5. A heat treatment apparatus as claimed in claim 4, in which the fluorine resin contains a small amount of ferric oxide.

6. A heat treatment apparatus as claimed in claim 1, in which the depth of the deep groove is more than the radius of the section of the cylinder.

7. A heat treatment apparatus as claimed in claim 1, the cylinder is provided with two deep grooves arranged in parallel with each other to pass two yarns.

8. A heat treatment apparatus as claimed in claim 1, in which the cylinder is provided with a shallow groove along the axial direction of the cylinder for receiving therein means for detecting the temperature of the cylinder and for regulating electric power to be supplied to the electrical heaters.

9. A heat treatment apparatus according to claim 8, in which the electric heaters are so constructed that their power consumption is larger at both end portions of the cylinder than that of the remainder of the cylinder.

10. A heat treatment apparatus according to claim 9, in which the power consumption of one end portion is larger than that of the other end portion.

References Cited UNITED STATES PATENTS 2,199,411 5/ 1940' Lewis 28 -62 X 2,495,053 1/1950 Conaway et al 34152 X 3,261,071 7/ 1966 Clendening et a1.

BERNARD A. GILHEANY, Primary Examiner. R. N. ENVALL, 'IR., Assistant Examiner.

US. Cl. X.R. 28-62; 26-3-3 

